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Re: 1990+ Fuel Pump Theory Posted by Justin VanAbrahams [Email] (#32) [Profile/Gallery] (more from Justin VanAbrahams) on Wed, 16 Mar 2016 21:37:20 In Reply to: Re: 1990+ Fuel Pump Theory, Landjet [Profile/Gallery] , Wed, 16 Mar 2016 19:28:07 Members do not see ads below this line. - Help Keep This Site Online - Signup |
That definitely seems possible, but frankly I just don't understand how it works in practice.
One side of that tee goes to the fuel rail, the other side right back to the tank. How does that configuration maintain pressure? Dumping half of the fuel pump output to open space is a big bleed! Does the size of the plastic hose act as a sufficient restriction to maintain pressure - is that the intent?
Second, why does that bleed from the pump outlet have its own tee - one leg which goes to the tank, the other to the bucket? If the point is to fill the bucket, why lose even more fuel to the tank versus return it all to the bucket?
Third, if the point of the tee off the pump outlet exists to keep the bucket full, why is that better than increasing flow through the entire fuel system and using the return from the rail to keep the bucket full? That's how the old two-pump system worked. Why the revision?
Obviously this design works because they stuck with it through the 9-5, *but* I have never seen another fuel pump like it, and why is it no other car has an even remotely similar double-bleed off the pump outlet?
It's very weird. And totally baffling!
posted by 12.195.130...
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